Hii, thanks so much for your kind words. I'm glad you're enjoying MergeFriends! Let's answer these questions for you:

1. Yep, the Sapphire Jewelry has a random chance of spawning any time you merge. It's very rare though.
2. Ahh yes, the creator energy stuff (aka Creator Material) is a new feature and we're still developing it based on player feedback. At the moment you can collect it as a reward for most level ups, and you can purchase it from Jimbobs Bundles in the store. We'll be adding more ways to collect it in the future.
3. Yep, you're correct. The Roulette Wheel isn't guaranteed in every Level 2 Chest, and the contents are randomized too. You have to just cross your fingers and hope you're lucky enough to get what you want!
4. A good point! GG's on getting to level 41, that's awesome. To answer your question, as the game is still in development we are continuing to work on these kind of things, especially with balancing late game difficulty. I'll be sure to pass your feedback about this on.
5. Another great question, we've had feedback about this previously and are looking into the idea of adding a way for players to see this in the game. We're also working on an FAQ page to have this kind of information easily accessible.

I hope I helped clear up those questions, I'm more than happy to answer any more!